Current computer graphics systems create images of graphics objects by first modeling the geometric and surface attributes of the objects in a virtual environment along with any light sources. The graphics systems can render images of the object in the virtual environment from the vantage point of a virtual camera. Great effort has been expended to develop computer graphics systems that allow objects with complex geometries and material attributes to be modeled. Also, a great effort has been expended to produce graphics systems that simulate the propagation of light through virtual environments to create realistic images.
Such modeling of objects typically involves generating a 3-dimensional representation of the objects using, for example, a polygon mesh to represent the surface of the object. Each polygon in a polygon mesh has vertices in space that define the perimeter of that polygon. Each polygon, thus, corresponds to a small portion of the surface of the object being modeled. To increase the resolution of the modeling, the number of polygons can be increased to represent minute nuances in the shape of the object.
The rendering of an image from such a polygon mesh can be computationally intensive and may not accurately represent the image of the real object in a real environment. The rendering is computationally intensive because for each polygon that corresponds to a portion of the object that is visible in the image, the graphics system would first need to identify that polygon as visible, determine the effects of the light sources, and then apply those effects to the image. The processing at each step can be computationally intensive. Moreover, such graphics systems have had very little success in determining the effects of a light source on the object. A complex object can be made of many different materials and there has been little success in accurately modeling the reflective characteristics of various materials.
Therefore, it has remained difficult or impossible to recreate much is of the complex geometry and subtle lighting effects found in the real world. To bypass the modeling problem, recently there has been interest in capturing the geometry, material properties, and motion of objects directly from the real world. This approach typically involves some combination of cameras, structured light, range finders, and mechanical sensing devices such as 3-dimensional digitizers and associated software. When successful, the results can be fed into a rendering program to create images of real objects and scenes. Unfortunately, these systems are still unable to completely capture small details in geometry and material properties. Existing rendering methods also continue to be limited in their capability to faithfully reproduce real world illumination, even if given accurate geometric models.
In certain systems, the traditional modeling/rendering process has been skipped. Instead, these systems capture a series of environment images and allow a user to look around an object from fixed vantage points. Although these captured images accurately represent the object from the fixed vantage points, the usefulness of such systems are limited because the objects can only be viewed from fixed vantage points. Attempts to interpolate an image of the objects from other vantage points have generally proved unsuccessful. It would be desirable to have a system for efficiently representing the complete appearance of an object so that accurate images of an object can be rendered from arbitrary vantage points.